Electrical resistance unit and terminal



Aug. 12, 1930. w. M, HEINA ELECTRICAL RESISTANCE UNIT AND TERMINAL FiledJan. 15, 1929 IN V EN TOR.

Patented Aug. l12, .1930

-UNITED STATES PATENT ,OFFICE WILLIAM M.' HEINA,` OF LONG ISLAND CITY,NEW YORK, ASSGNOR T0 AUTOMOBILE RADIO CORPORATION, A CORPORATION 0FDELAWARE V f vELECTRICAL RESISTANCE UNIT AND TERMINAL Application ledJanuary 15, 1929. Serial No. 332,621.

This invention relates to an electrical resistance unit and terminal forattachment to the end of an electric wire conductor.

Among the objects of this invention is the 6 provision of a rugged,compact and neat device of the character described whichshall comprisefew and simple parts, permittlng ease of assembly and handling, whichshall be comparatively inexpensive to manufacture and shall yet bepractical and efficient to a high degree.

Otherl objects of this invention, will 1n part be obvious and in parthereinafter pointed out.

The invention accordingly consists 1n the features of construction,combinations of elements, and arrangement of parts which will beexemplified in the construction hereinafter described, and of which thescope of application will be indicated in the following claims.

In the accompanying drawingfin which 1s shown one of the variouspossible illustrative embodiments of this invention,

Fig. 1 is a longitudinal partial cross-sectional view of a deviceembodying the invention attached to a piece' of insulated wire, showingthe parts only partially assembled,

Fig. 2 is a longitudinal view of the assembled device with parts brokenaway to dlsclose the interior construction.

Referring in detail-to the drawing, 10 des# ignates a portion of anordinary iiexible -lead or conductor, here seen to comprise a strandedwire 11 covered by the usual insulating coating 12. Attached to one endof said conductor 10, in a manner hereinafter appearing, is a highresistance unit 14 adapted for various uses such as, for example,attaining a high damping co-eficient for an electric circuit.

Saidy unit 14 comprises a member 15 havy ing a high resistance to anelectric current,

said member in the form'shown herein, comprising .a cylindrical post orbar made of carbon, preferably graphite. Received over one end portion15a of said bar 15 is a c lindrical, metallic cap member 16 tightly ttedthereon. The end wall 1.6"L of said ca is slightly spaced from theouterend sur ace is suitably soldered to' said end Wall for per-v manentlyconnecting the lead 10 to the'ihigh resistance bar 15. Receivedover theopposite end 19 of said bar 15, is a metallic member -20 having-asocketed portion 21 for snugly receiving said end portion 19. Saidmember 20 is provided with a flanged head 22 and a flat bifurcated blademember or terminal connector 28 extending therefrom which serves as aterminal member for connecting the lead 1,0 and unit 14 to any suitablebinding post or terminal (not shown). The end portion 19 of the graphitebar v15 may be fused with the socket 21 o r mayy simply have a snugsliding fit therein.

For firml anchoring the member 20 to the bar 15 and or protecting thelatter, the socketed portion 21 may be provided with an external thread25 and a protective tubular casing or sleeve 26 is provided of moldable,insulating material such as porcelain, vulcanized rubber,phenol-condensate products, or the like, said casing 26 having aninternally threaded end portion 27 adapted to receive and coact withthreads 25 of member 20. The internal diameter of the casing 26 issufiicient to permit it to be slid over the bar 15 and the cap 16 forthe threading operation. The end portion 28 of the casing 26 remote fromthe substantially abut the outer peripheral portion of the cap wall. 16awhen said tube is` screwed to the end member 20, to press and bind theparts in good electric contact.

' The manner of assembling the unit 14 will now be apparent. The casing26 is first fitted on the conductor 10. The end portion 18 of the wire11 is then connected to the cap 16, the` latter being then fitted on the'resistance bar 15. The terminal member20 may then be Fig. 1 o thedrawing, and screwed to the threaded portion 21 ofthe terminal member20. The resistance bar 15 is thus rmly recfitted on the outer end 19'ofsaid bar 15, andV the casin then pushed toA the left, lookingat tainedwithin the "casing 26, good electrical contact assured, and displacementof the terminal member 2O prevented, by the abutting contact between theshoulder29 and the cap 16. In the assembled position the tubular casingacts as an insulator and also as a handle for the unit when connectingor unconnecting the same to a bindin post or terminal.

Obviously, the hig resistance element may take the form of a thin coiledwire or any other suitable form. Y

It will thus be seen that there is provided a device in which theseveral objects of this invention are achieved, and which is welladapted to meet the conditions of practical use.

As various ossible embodiments might be made of the above invention, andas various changes mi ht be made in the embodiment set forth, it 1s tobe understood that all matter herein set forth or shown in th'eaccompanying drawing is to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention I claim as new and desire to secureby Letters Patent:

l. A resistance unit and terminal for attachment to an electrical wireconductor, comprising a terminal connector, a resistance element havingone end in electrical contact with l said' terminal connector, and atubular casin for the resistance element having at one en an openingthrough which a wire conductor may extend for connection to the otherend of said resistance element, the other end of said casing beingdetachably connected to said terminal connector, said tubular casinghaving an inner shoulder coacting with the resistance element when theparts are in assembled relation.

2. A resistance unit and terminal for attachment to an electrical wireconductor, comprising a terminalconnector having a socketed portion, aresistance element having one end fitted in said socketed portion, a captted on the other end of said resistance element and adapted toelectrically connect the latter to a wire conductor, and a tubularcasing for the resistance element having at one end an opening adaptingit for slidable movement over said Wire conductor, said end of saidcasing having an inner shoulder coacting with the capped end of theresistance element for holding the parts in tight electrical contact,when in assembled relation, and means at the other end of said casin fordetachable connection with said electrical connector.

3. A resistance unit and terminal for attachment to an electrical wireconductor, comprising a terminal connector having a socketed portionexternall threaded, an elon ated resistance element fitted into s'aidsoceted portion, a metal cap fitted on the other end of said resistanceelement and havin an opening therein through which the end of a wire Intestimony-whereof I aix my si ature.

WILLIAM M. NA.

